The Centurions used by Israel were obtained from various source nations aside from Britain. As such they were of various Marks: 3, 5, etc. These were the basis for the Sho't modifications. And while they would be upgunned, re engined, etc. while in IDF service the basic hull and turret differences between the different Marks would remain. So an orginal Mk.3 hull/turret could be seen with a 105 gun and Continental Diesel later in its IDF service life. I dont have hard timelines as to when what modifications in main gun armament and such were made, so I cant be of too much help as to if any older gun tubes would be seen in 1967. But by 1973 they certainly were all 105mm armed but still a mix of petrol and diesel engined types. Photos are pretty clear on this.
This site is a good place for reference pics though
http://idfmodelling.free.fr/
F is for FIRE, That burns down the whole town!
U is for URANIUM... BOMBS!
N is for NO SURVIVORS...
- Plankton
LSM